Interpretation of response categories in patient-reported rating scales: a controlled study among people with Parkinson's disease

Table 1 Descriptive response category VAS data

		Mean	SD	95% CI	Median	q1-q3	Min-max
Frequency:
f1	Seldom (sällan)	25.3	16.4	21.8-28.8	20	14-31	3-72
f2	Occasionally (vid enstaka tillfällen)	30.8	20.5	26.4-35.2	24	15-40	4-82
f3	A little of the time (lite av tiden)	33.7	18.0	29.9-37.6	28	21-46	7-75
f4	Some of the time (en del av tiden)	44.7	16.8	41.1-48.3	43.5	33-54.5	15-81
f5	Sometimes (ibland)	45.9	17.5	42.2-49.6	48	33-52	14-91
f6	A good bit of the time (en hel del av tiden)	71.1	18.3	67.2-75	75	67-82	5-98
f7	Often (ofta)	74.7	12.7	72.0-77.4	76	70-83	32-98
f8	Most of the time (största delen av tiden)	76.8	16.3	73.3-80.3	80	71-89	21-99
Intensity:
i1	A little bit (en aning)	21.9	15.2	18.6-25.1	19	11-28	2-76
i2	Slightly (lite)	24.0	14.1	21.0-27	21	14-27	2-78
i3	Somewhat (något)	29.8	17.4	26.1-33.6	26	17-37.5	2-83
i4	Moderately (måttligt)	42.1	14.3	39-45	44	31.8-50.2	6-86
i5	Quite a bit (ganska mycket)	73.5	11.9	71-76.1	74	66-81	38-96
i6	A lot (mycket)	73.7	14.1	70.7-76.6	76	69-82	24-99
Agreement:
a1	Disagree (stämmer inte)	15.5	21.2	11-20	7	2-19	0-81
a2	Mostly false (stämmer inte särskilt bra)	28.0	17.7	24.2-31.8	23	16-34	4-84
a3	Don't know (osäker)	38.9	19.1	34.8-43	40	24-50	2-84
a4	Do not agree or disagree (varken stämmer eller stämmer inte)	43.2	16.0	39.8-46.6	49	41-52	0-71
a5	Mostly true (stämmer ganska bra)	70.7	14.7	67.6-73.8	74	63-81	32-94
a6	Agree (stämmer)	78.3	21.9	73.6-83	86	64-95	13-100
a7	Strongly agree (stämmer helt)	86.7	18.2	82.7-90.6	95	82.5-99	22-100

Visual analog scale (VAS) values for the 21 rating scale response categories as determined by people with Parkinson's disease and control subjects. Categories are organized in ascending order (from lower to higher mean VAS values). Swedish category wordings used in this study are given in parentheses ^a
^a There were two instances of missing VAS data among people with Parkinson's disease (both involving category a7) and six missing VAS values among controls, including one each for categories i3 and i4, and three missing values for category a3.
SD, standard deviation; CI, confidence interval; q1-q3, 25^th and 75^th percentiles.

ISSN: 1477-7525